(1) Field of the Invention
This invention relates to a transmission system for vehicles.
(2) Prior Art
In four wheel drive (4WD) and certain conventional drive vehicles, it is required that at least one driving wheel has traction when one or more of the other driving wheels begin to spin to enable the vehicle to continue to move. Locked differentials provide the necessary type of drive but make cornering difficult (or almost impossible), while the limited slip differentials (LSD) presently available have proved generally unsatisfactory in practice.
With four wheel drive vehicles, the problem of "differential wind-up" is also of concern as the front wheels must rotate upto e.g. 25% faster than the rear wheels when turning on full lock as they travel around greater radii.